Symmetrical drawing-board



UNITED STATES PATENT OFFICE.

CHARLES DIEDRIOH HILLMAN, OF LOUISVILLE, KENTUCKY.

SYMM ETRICAL DRAWING-BOARD.

Specification forming part of Letters Patent No. 50,583, dated October 24, 1865.

To all whom 'it may concern.'

Be it known that I, CHARLES DIEDRIOH HILLMAN, of Louisville, in the county of Jef'- feison and State of Kentucky, have invented a new and useful or Improved Symmetrical Drawing-Board; and I do hereby declare the same is fully described and represented in the following specifica-tion and the accompanying drawings, ot' which- Figure l is a perspective View; Fig. 2, a plan of one of the elastic cords with its end fastenings, and Fig. 3 a section of said drawing-board in a folded state.

The nature ot' my invention consists ot'joining two drawing-board frames together by means of hinges` pivoted on thumb-screws, so that the two frames can be so adjusted as to form to each other any required angle and rmly held at such angle. by means ofthe set or thumb screws. Furthermore, one of the frames (which I shall designate the haseframef) has inserted therein a panel, on which is placed a sheet of paper having lines drawn thereon representing,l different-colored squares, while the opposite or top frame has elastic cords passing,` over its face, which represent squares corresponding in size and color. Said top frame has no panel, but is open at the back for reception of adrawing. Now, by placing a sheet of transparent paper on the base-frame it is plain to he seen that a copy ofthe drawing in the top fratrie can be made with much ease and rapidity on said transparent sheet. As the learner progresses every other line may be removed, and thus a perfect acquaintance with the art of drawing, from originals acquired.

In the said drawings, A is the base-frame with its turn-buttons B B for sustaining in place thepanel O, on which is laid a sheet of paper, D, representing different-colored squares E E, &c.

The top frame, A', is connected to the baseframe by means ofhinges F F and thun] b-screws G G, by means of which the top frame can be adjusted to and held at any required angle to the hase-frame, as already explained. The top frame, A', is recessed on its under side for reception of thin strips of metal H H, said strips being` notched and slightly raised at such notches for reception of the small triangular stay-pieces I I, to which the ends of the elastic cords are fastened. The said cords, when placed in position, represent squares E E', corresponding,` in size and color to those on the hase-frame.

The two frames can be folded book-fashion when not in use, as shown in the drawings.

Vhat I claim, and desire to secure by Letters Patent, is

The above-described symmetrical drawingboard, substantially as and for the purpose de scribed.

In testimony whereot l have hereunto setmy signature.

CHARLES DIEDRIOH HILLMAN.

Witnesses WILLIAM SoHENK, ERNST SAUERMANN. 

